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Liz's original questions were:
Are there any municipalities with bio-diesel plants that are collecting waste cooking
oil from homes and restaurants and turning it into fuel? Is it an efficient process? Affordable?
Relatively clean? What happens to this kind of waste in Halton? Would it be feasible for our municipality
to set up?

This is a work in progress and will likely get updated frequently as the research progresses.

What is biodiesel?

Biodiesel is the name given to a diesel engine compatible fuel which can be produced from vegetable oil. The most common biodiesel is methy ester, which is produced by reacting vegetable oil with methanol in the presense of a catalyst. While the processing is more difficult to control one can also produce ethyl esters by substituting ethanol for the methanol in the process. The process is called transesterfaction and was rediscovered in Austria and South Africa in the early 1980 after being invented almost 100 years earlier. This process has the advantage that it can easily be scaled from batches in the kitchen sink to large scale factories.

What are the raw materials needed for biodiesel

The basic raw material needed is vegetable oil. Most biodiesel today is made from first use canola oil. Canola has an impressive yield of 1190 litres/hectare but it isn't the highest yield vegetable oil crop suitable for biodiesel. Today that title is held by palm oil at 5950 litres/hectare. Between 1976 and 1998 the NREL in US researched the potential for algae as a biodiesel feedstock. They calculated that algae ponds could yield an impressive 34000 litres/hectare.

In addition to vegetable oil most biodiesel processes use between 200-400ml of methanol for each litre of vegetable oil. Most methanol today is made from non renewable natural gas, but it can be made from biomass such as wood. The most common catalyst is lye (NaOH). The catalyst usage is around 4ml per litre of vegetable oil.

What are the environmental issues with biodiesel?

Biodiesel itself is remarkably benign. It is about as biodegradable as sugar and about ten times less toxic than table salt. Studies have shown that a biodiesel spill into the environment would totally biodegrade in a matter of a few weeks.

Having said this biodiesel is rarely used unblended today. One reason is that biodiesel can easily be blended in any ratio with petrodiesel. The city of Brampton uses B5 (5% biodiesel, 95% petrodiesel) as their winter blend and B20 (20% biodiesel) as their summer blend. The toxicity of a biodiesel blend would be dominated by the toxicity of the petrodiesel component of that blend.

While biodiesel typically only has 90% of the energy of petrodiesel it does produce significantly less toxic pollutants when burned in an engine.

The manufacturing of biodiesel produces significant quantities of glycerin as a byproduct. Glycerin is used for such things as soaps and cosmetics, but the current biodiesel market has flooded this glycerin market to a saturation point. It is possible to convert glycerin into useful products like windshield washer fluid. One company in the Netherlands is piloting a process to convert glycerin to methanol: a feedstock in the biodiesel process.

Can waste cooking oil get recycled into biodiesel?

The short answer is yes, lots of people are doing this today. It is estimated that if 50% of the waste cooking oil in the US could be recovered and converted into biodiesel one could meet 2% of the transportation fuel needs in the US. However, in a smaller nich market like Oakville and Oakville Transit that percentage could be higher.

San Francisco has recently embarked on a city wide waste oil collection/recycling program. One of their motivations is the potential reduction in the $3.5M tab to clean out clogged sewer pipes when that waste is improperly disposed of.

It would seem that Brampton has recently instituted a similar program.

Is biodiesel economic?

This is a tricky question because most biodiesel today exists because it is subsidized. Ontario has an attractive subsidy program and the city of Brampton has determined that biodiesel makes sense economically for them in B5 to B20 range.

A very active group in North Carolina has been producing biodiesel from waste vegetable oil for a number of years now. They make a profit selling their fuel to members at $3/gallon.

What about doing this in Oakville?

Oakville transit used 2.4 million litres of diesel fuel in 2006. At a B20 ratio this would require almost 0.5 million litres of biodiesel to be available.